1. Field of the Invention
This invention relates to multi-component fan assemblies for use in blowers and the like.
2. Description of the Prior Art
In one known type of multi-component fan assembly, as disclosed for example in U.S. Pat. Nos. 2,654,529 (Smith); 3,077,811 (Moore); 3,224,078 (Mayne); and 5,269,655 (Chang), at least some of the fan components are joined together by means of some form of permanent material deformation. This complicates assembly and disassembly by requiring the use of special tools or presses. In most cases, disassembly entails permanent destruction of some components.
In another type of known multi-component fan assembly, as disclosed for example in U.S. Pat. Nos. 4,256,435 (Eckel) and 5,281,095 (Glynn), blade components are assembled onto and protrude radially from a circular hub. In Eckel, the hub includes mounting blocks riveted between two retaining discs, with the blades being screwed to the mounting blocks. The use of multiple retaining discs contributes unnecessarily and disadvantageously to the overall weight and cost of the assembly, and also complicates assembly procedures. In Glynn, the hub includes a single disc to which the blade segments are attached by means of a retaining ring which can either be of a unitary split design, or which can be made up of multiple segments.
The radial disposition of the blades in the central plane of the hub in both the Eckel and Glynn arrangements limits the extent, if any, to which the fan assembly can be telescoped over the drive motor to achieve overall axial compaction.
One objective of the present invention is the provision of a fan assembly made up of a minimum number of components which can be easily assembled without permanent material deformation, and without the need to employ special tools or presses.
A companion objective of the present invention is the provision of a multi-component fan assembly having a hub in the form of a single circular disc, with a segmented wall extending axially in cantilever fashion from the periphery of the disc. The disc and wall segments are molded non-metallic components, with the wall segments serving as supports for the fan blades. The wall segments are interlocked to the disc as well as to each other by snap-engaged metal retaining rings which can be removed to accommodate disassembly of the fan components.
These and other objects, features and advantages of the present invention will become more apparent as the description proceeds with reference to the accompanying drawings, wherein: